Machine walking device



Dec. 27, 1949 Filed July 24, 1947 M. ARMSTRONG MACHINE WALKING DEVICE 3Sheets-Sheet 2 SQ 0 re f'zz enZ or 'ffr'zuibz (29-7715 7*0 Dec, 2?, 1949M. ARMSTRONG MACHINE WALKING DEVI CE 5 Sheets-Sheet 3 Filed July 24,.1947 7275071 irwy g Patented Deo- 2 19 9 UNITED STATES PATENT OFFICE2,492,548 MACHINE WALKING DEVICE Mei-win Armstrong, Hinsdale, Ill.Application July 24, 1947, Serial No. 763,229

Claims.

The present invention relates to a traction mechanism of the stepping orwalking type for propelling heavy machines, such as excavators whichrequire relatively large bearing areas for support and where for serviceit is desirable to have few moving parts in contact with the ground.

It is an object of the present invention to provide a traction mechanismthat gives improved walking motion. This is accomplished while at thesame time the construction is simplified and is well adapted for use onlarge and heavy machines.

The foregoing constitute some of the principal objects and advantages ofthe present invention, others of which will become apparent from thefollowing description and the drawings, in which Fig. 1 is a sideelevational view of a machine, such as a drag-line excavator embodyingthe present invention, the shoes and legs being disposed in the raisedor carrying position;

Fig. 2 is a fragmentary view corresponding to Fig. 1 but illustratingthe shoes and legs advanced and lowered to the ground at the beginningof the step just before the body is lifted;

Fig. 3 is a view corresponding to Fig. 2 but illustrating the shoe inengagement with the ground and the machine body lifted ready foradvancement during the next 90 rotation of the crank shaft;

Fig. 4 is a plan view of the machine illustrated in Fig. 1;

Fig. 5 is an end view of the machine;

Fig. 6 is an enlarged sectional view of a detail taken on line 6-6 ofFig. 1; and

2 tracks l4 and I5. As best shown in Fig. 4 the body 12 includes a pairof outwardly projecting housing portions I! that are on opposite sidesof the body i2.

Extending entirely across the body l2 and journalled in the housingportion I1 is a horizontally disposed shaft IS, the bearings for theshaft being illustrated at l9. Disposed parallel to the shaft !8 andmounted in the machine body I2 is a second shaft 20 journalled at itsopposite ends as indicated at 21. Mounted adjacent to one end of thisshaft 20 is a drive gear 22. A motor or engine 23 is housed in themachine body l2 and is provided with a pinion 24 that meshes with thedrive gear 22. A pinion 25 is mounted on the opposite end of the shaft20 and is adapted to mesh with a gear 26 that is mounted on the shaftI8. Thus the motor 23 is adapted to drive the shaft 18 through thepinion and gear 24, 22, shaft 20 and pinion-gear set 25 and 26.

Disposed on the opposite sides of the machine body l2 are feet or shoes21 (see Figs. 1, 4 and 5).

. Each foot 21 is provided with upstanding ear Fig. 7 is a sectionalview taken on line 1-1 of Fig. 6.

The present invention may be used in practice in various ways. Forpurposes of illustration one embodiment only is shown and thisembodiment is illustrated as applied to a drag-line excavator. Obviouslymany modifications may be made in the embodiment shown without departingfrom the intended scope of the invention. 7

Referring now to the drawings the invention. is illustrated as appliedto a drag-line excavator generally indicated at [0 (in Fig. 1)- thatincludes a body portion 12 that is mounted on a main base i3. A trackmember I4 is supported on the base 13 and a complementary track. member:5 is supported on the underneath facev of the body l2. Wheels orvrollers l3 are disposed between the track members l4 and I5 so that thebody I2 is adapted to rotate about the base l3 by virtue of the rollerslfi operating between the portions 28 (see Fig. 1) to which arepivotally connected the lower end of a leg 29 by pin 30. Mounted on eachend of the shaft I8 is an eccentric or crank 3i that is provided with acrank arm 32, the end of which arm is journalled in the upperor free endof the leg as at 33.

Referring now to Fig. 4 a shaft 34 is journalled on its opposite ends asat 35 in each of the housing portions ll of the machine body l2 and eachof these shafts extends parallel to the main shaft l8. For purposes ofthis description the direction of movement of the machine body I2 isfrom right to left as indicated by the arrow A. in Fig. 1 so that withrespect to the direction of movement of the machine the left hand edgeof the body l2 will be referred to as the forward edge and is identifiedby the reference character 36. Thus 4 the shaft 34 is rearwardly spacedwith respect to the shaft I8. Mountedon the outer end of each of theshafts 34 is a crank 31 having a crank arm 38. Journalled to thefree'end of the crank arm 38 is a connecting rod or link 39 that ispivotally connected to an ear 4| (see Fig. 4) on the leg 29 intermediatethe upper and lower ends of the leg.

Again referring to Fig. 4 a suitable drive such as a sprocket chaindrive generally indicated at 42 is provided between the shafts l8 and 34so that each of the shafts 34 receives its rotated power from the shaftl8 and is driven at the same speed as the shaft I8.

There is thus described a traction mechanism 3 that is simple and yeteffective for moving large and heavy machinery. As shown in Fig. 1 theshaft l8 normally operates in a counterclockwise direction and as shownthe crank 3| is rotated to the first 90 from a substantially horizontalposition to a vertical upright position where each foot 21 is raised oithe ground to its uppermost position, each foot advancing somewhat in ahorizontal direction during this first 90. "During, the

next 90 rotation of the crank 3| the shoes or feet 27 are advanced andplaced on the ground as indicated in Fig. 2. The cranks are thenrotatedjz 1. to an additional 90, during which timepne. edg

of the base I3 is raised off the ground as indioperation of the cranksthe machine is moved 4 the leg 21. The lower face of the bearing member5! is seated on a bearing block 51, there being provided cooperatingarcuate engaging faces. The bearing block 51 is slidably supported on aplate 58 that in turn rests on a pair of I-beams 59. The plate 58 ischanneled at 60 to hold the bearing block 5'! in sliding relationship.The block 57 is apertured at El to receive rod 62 that projects beyondeach ear 28. Compression springs 53 are mounted on the ends of each rod-62 and a spring seat 6t is threaded onto each end of the rod 62. Eachspring 63 is held between one of the seats .54 and the adjacent ear 28.These springs cated in Fig. 3 and then during the. next-90 forwarddragging the right hand end -(Fig;-' 3-) of the base along the ground.As the crankrotates from the position shown in solid lines in Fig. 3 theforward edge ofthemaohine base! 3 is.lo.w.ered until it finally engagesthe ground. wherethe entire machine has .advanceda:prcdetermineddistancedepending upon the relati'onship...between the ,yarious .arms andcranks. The. operation. can then be repeated so as to continue'theadvance: mentof. the machine.

During. this operation of. the main...crank..3l the auxiliary shaft.Stiscaused to. operate at the. same speed as the..main.shaf.t. I8 so asto turn. the cranks 31.. These .cranks- 31 throughtheir respective links39 serve to guide the legs 29 and to impart to the legs a substantiallyhorizontal posi: tion. Thusthe: cranks 3i provide vertical lift to theshoesor feet; 27 and the cranks-31' impart horizontal motion:

Mounted .on topof-eachof the-housing portions 11 of the; machine body-L2is an equalizer generally indicated at 43. that includes a pair of,spaced cables 44 fixedat, theirsldwer endslas at 40. to one of thefeetor shoesv 21 at positions, equidistant from the ends of the shoes.Each-of. these cables 44 passes over av pulley 45 (Fig. 5) thatisdisposed substantiallyvertically. above the shoe 2 and-then passesovera second pulley 4B. --;A weight. 41 is fixed to the free-end-rofeachcable 44. 'This weight is adapted to slide :up and down on aninclined surface 48 that is formed on a frame member; 39. Oneend; ofthis frame.member..-4.9 is pivotally secured to a bracket; 5.0 that ismounted on top of thehousingsi'l. As best shownin Figs. 1 and "5 theforwardendv of each of the frame members .419 is provided .with' an.I-beam 65 that rests on top of a roller; 66 that is journalled in anglemembers 6'l. -.+These-angle meme hers 5? are mountedion top of: each: ofthe. legs 29 so that-the forward end :of' each-of the :frame membersceis actually supported on theadjacent leg 29. The weights 4! on thecables 44 are of equal weightso that as the foot or. shoe 2:! is raised:

'above the ground, these'weightsll through their.

respectivecables: 44 arenfreeto slide. on the sure face as and; if theshoe tilts: due to an accumu+- lation of mud or theilike; theweightronthecorresponding side ,comesto rest on 'aistcrxizt so that theotherweightrcan:act to returntthe; foot .or. shoe 2'! to thehorizontalpositionti;

Each of the legs 29 is provided at its lower end; withabearing member51, shown-in Figs". (5 and.7,

that; comprisesza pair .of: plates .52. and .53 fastened:

together as at 54. This;bearinamembcrti has: a spherical socket; 55 inwhich is .rotatably2 mounted a rotatablamember. 56 having sphericalsurfaces adapted to cooperate withthe faces55.-

The. rotatable member 55-: isapertured to receive the pin 30. This pin30 is held in the ears 28 on 63 normally center the bearing block 5?between the ears .28 but permit sliding movement of the block to takeplace along the rods 62.

Throughout this description the members 3| and 3-1 have been referred toas cranks. It is recognized, of course, that conventional eccentrics,other than. true cranks maybe employed, it beingimportantonly that,eccentricityibe pro.- vided.tofurnishalever or crank arm.

With, the arrangement thus .describedthe legs 29 are, disposed inasubstantially vertical posi-, tion throughout the lifting portionofthe-cycle ofcrank 3! but is moved to a sloping or leaning position inthe direction of movement of the machine body it during the last portionof the cycleof the crankv 3! While themachine. body is being lowered.This leaning conditionof the legs 29 isv brought aboutby virtue of.thefact that the crank arm for crank 31 is longer thanthe. crank arm forcrank 31. Thus .the legs serveas direct columns duringlifting of the -machine body, but serve to easethe weight to the, ground rather than toallow the. weight to dropfreely from the mechanism height.

I claim:

1. The combination of aframe, substantially vertically disposed legs ateach side of: the frame, a foot pivotally secured to the lower end ofeach leg, crank means includinga crank arm disposed adjacentto the upperend .of each leg, means on the frame mounting each- ,crank for rotationabout a horizontal axis, each leg being mounted adjacent-to its upp rend on a crank-warm and of sufficient length to bear the feet onthe..ground,- second crank means includinga crank armv spacedlongitudinally of the frame with'respect. to each of the firstmentionedwcranks, means mounting each of the second cranks for:ltotationi about a horizontal axis,power=means. mounted on the frameconnected in driving relationship with the cranks, and alink; connectingthe. crank armor each of the second cranks and the adjacent legintermediate the upper and lowerends. of the leg.

2. The combination of a frame-substantially. vertically disposed legs ateachside-ofthe frame, aw-foot pivotally secured tothe'lower end of each.leg, crank means including a crank arm disposedadjacentxto theupner-end'of eachleg,v means on the frame mounting: eachgcrank, forrotation about va horizontal axis, eachleg being; mounted adjacent-toits upperencl on a crankarm and .of sufficient length to bear the feeton the; ground, second'crank means including a crank, arm spacedlongitudinally of the frame withrespect to each. of the firstrnentionedcranks: and dis posed substantially parallel therewith; means mountingeach of thesecond cranks for rotation about a horizontal axis, powermeans mounted on the frame: connected. in driving, relationship with thecranks,..and a. link. connecting= thecrank arm of each of the secondcranks and the adjaof the leg.

3. The combination of a frame adapted to move in one directionandhavinga leading edge with respect to the direction of travel,substantially vertically disposed legs at each side of the frame spacedrearwardly from the leading edge, a foot pivotallysecured tothe lowerend of each, leg, crank means spaced rearwardly from the leading edgeincluding a crank arm disposed adjacent to the upper end of each leg,means on the frame mounting each crank for rotation about a horizontalaxis, each leg being mounted adjacent to its upper end on a crank arm,second crank means including a crank arm spaced further away from theleading edge than the first crank means, means mounting each of thesecond cranks for rotation about a horizontal axis, power means mountedon the frame connected in driving relationship with the cranks, and alink connecting the crank arm of each of the second cranks and theadjacent leg intermediate the upper and lower ends of the leg.

4. The combination of a frame, substantially vertically disposed legs afoot pivotally secured to the lower end of each leg, crank meansincluding a crank arm disposed adjacent to the upper end of each leg,means on the frame mounting each crank for rotation about a horizontalaxis, each leg being mounted adjacent to its upper end on a crank armand of sufilcient length to bear the feet on the ground, second crankmeans including a crank arm spaced longitudinally of the frame withrespect to each of the first mentioned cranks, means mounting each ofthe second cranks for rotation about a horizontal axis, power meansmounted on the frame connected in driving relationship with the cranks,and a link connecting the crank arm of each of the second cranks and theadjacent leg intermediate the upper and lower ends of the leg, and meanson the frame and operatively connected to each foot for maintaining thefoot horizontal.

5. The combination of a frame, substantially vertically disposed legs ateach side of the frame, a foot pivotally disposed to the lower end ofeach leg, crank means including a crank arm disposed adjacent to theupper end of each leg, means on the frame mounting each crank forrotation about a horizontal axis, each leg being mounted adjacent to itsupper end on a crank, second crank means including a crank arm spacedlongitudinally of the frame with respect to each of the first mentionedcranks, means mounting each of the second cranks for rotation about ahorizontal axis, power means mounted on the frame connected in drivingrelationship with the cranks, a link connecting the crank arm of each ofthe second cranks and the adjacent leg intermediate the upper and lowerends of the leg, means providing linear movement of the foot on the leg,and means on the frame and operatively connected to each foot formaintaining the foot horizontal.

6. The combination of a frame, substantially vertically disposed legs ateach side of the frame, a foot pivotally disposed to the lower end ofeach leg, crank means including a crank arm disposed adjacent to theupper end of each leg, means on the frame mounting each crank forrotation about a horizontal axis, each leg being mounted adjacent to itsupper end on a crank, secondcrank means including a crank arm spacedlongitudinally of the frame with respect to each of at each side of theframe, a

, the first mentioned cranks, means mounting, each zontal axis, powermeans connected. in driving relationship withthe cranks, alinkconnectingthe crank, arm of each of the second cranks for-rotationabout a horimounted on the frame of the second cranks and the adjacentleg inter- ,mediate the .upper and lower ends of the leg,

means providing linear movement, of thefoot on the leg, and means .ontheframe and operatively connected to each foot for maintaining the foothorizontal, said last named means including an equalizer arm, meanspivoting one end of said equalizer arm on the frame, and means mountingthe other end of the equalizer arm for sliding movement on the top ofthe leg.

7. The combination of a frame, substantially vertically disposed legs ateach side of the frame, a foot pivotally secured to the lower end' ofeach leg, crank means including a crank arm disposed adjacent to theupper end of each leg, means on the frame mounting each crank forrotation about a horizontal axis, each leg being mounted adjacent to itsupper end on a crank arm aforesaid and of sufficient length to bear thefeet on the ground, second crank means including a crank arm spacedlongitudinally of the frame with respect to each of the first mentionedcranks, means mounting each of the second cranks for rotation about ahorizontal axis, power means mounted on the frame connected in drivingrelationship with the cranks, and a link connecting the crank arm ofeach of the second cranks and the adjacent leg intermediate the upperand lower ends of the leg, and means on the frame and operativelyconnected to each foot for maintaining the foot horizontal comprising anarm pivotally mounted on the frame and adapted to move up and down witheach foot and weighing means operatively connected to the foot andactuated by the pivoted arm to maintain the foot in the horizontalposition.

8. The combination of a body mounted on a ground bearing base andadapted to rotate about a vertical axis with respect to the base, a pairof parallel eccentric driving elements mounted on each side of the bodyand spaced longitudinally of each other with respect to the body, a legon each side of the body trunnioned at its upper end to one of theeccentric elements and at its lower end to an auxiliary ground bearingfoot, a link connecting said leg to the other eccentric element of saidpair, and power means on the body rotating each eccentric element abouta horizontal axis.

9. The combination of a body mounted on a ground bearing base andadapted to rotate about a vertical axis with respect to the base, a pairof parallel eccentric driving elements mounted on each side of the bodyand spaced longitudinally of each other with respect to the body, a legon each side of the body trunnioned at its upper end to one of theeccentric elements and at its lower end to an auxiliary ground bearingfoot, a link connecting each of the second eccentric elements and theadjacent leg intermediate the upper and lower ends of the leg, and powermeans on the body for rotating the eccentric elements in the samedirection and at the same rotative speed.

10. The combination of a body mounted on a ground bearing base andadapted to rotate about a vertical axis with respect to the base, a pairof parallel eccentric driving elements mounted on each side of the bodyand spaced longitudinally of each other with respect to the body, a legon each side of the body trunnioned at its The following references areof recorg'jimthe

